Touch display device

ABSTRACT

A touch display device includes a reflective display module, a touch sensing layer, a light guide member, a ground shielding layer, and a first adhesive layer. The touch sensing layer is disposed on a display surface of the reflective display module, and the light guide member is disposed between the reflective display module and the touch sensing layer. The ground shielding layer is in contact with the light guide member and located between the reflective display module and the touch sensing layer. The ground shielding layer electrically connects to one of the reflective display module and the touch sensing layer to electrically connect to a ground potential through the one of the reflective display module and the touch sensing layer. The first adhesive layer is disposed between the light guide member and the reflective display module, and is located between the ground shielding layer and the reflective display module.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the priority benefit of Taiwan applicationserial no. 111105524, filed on Feb. 16, 2022. The entirety of theabove-mentioned patent application is hereby incorporated by referenceherein and made a part of this specification.

BACKGROUND Technical Field

The disclosure relates to a display device, and more particularly to atouch display device.

Description of Related Art

With the rapid development of technology, manufacturers of touchdisplays, home appliances or in-vehicle products have a tendency to usetouch modules to replace traditional mechanical buttons as a newgeneration of input interfaces. However, the touch module still cannotcompletely avoid electromagnetic interference, and the display signal ofthe display may easily cause the touch module to sense the change of thecapacitance value, thereby generating noise and affecting the sensing ofthe touch module.

SUMMARY

The disclosure provides a touch display device that is light and thinand achieves a good anti-noise effect.

The touch display device of the disclosure includes a reflective displaymodule, a touch sensing layer, a light guide member, a ground shieldinglayer, and a first adhesive layer. The touch sensing layer is disposedon a display surface of the reflective display module, and the lightguide member is arranged between the reflective display module and thetouch sensing layer. The ground shielding layer is in contact with thelight guide member and located between the reflective display module andthe touch sensing layer. The ground shielding layer electricallyconnects to one of the reflective display module and the touch sensinglayer, so as to electrically connect to a ground potential through theone of the reflective display module and the touch sensing layer. Thefirst adhesive layer is disposed between the light guide member and thereflective display module, and is located between the ground shieldinglayer and the reflective display module.

In an embodiment of the disclosure, the light guide member of theabove-mentioned touch display device includes a light guide plate and alow refractive index layer. The low refractive index layer is disposedon the light guide plate, and the refractive index of the low refractiveindex layer is smaller than the refractive index of the light guideplate.

In an embodiment of the disclosure, the ground shielding layer of theabove-mentioned touch display device is in contact with the lowrefractive index layer.

In an embodiment of the disclosure, the light guide plate of theabove-mentioned touch display device has a light incident surface, afirst surface, and a second surface. The first surface and the secondsurface connect to the light incident surface and are opposite to eachother, and at least one of the first surface and the second surface hasmultiple optical microstructures.

In an embodiment of the disclosure, the thickness of the low refractiveindex layer of the above-mentioned touch display device is greater thanthe thickness of the optical microstructures.

In an embodiment of the disclosure, the low refractive index layer ofthe above-mentioned touch display device includes a first low refractiveindex layer and a second low refractive index layer. The first lowrefractive index layer and the second low refractive index layer aredisposed on the first surface and the second surface of the light guideplate, respectively.

In an embodiment of the disclosure, the above-mentioned touch displaydevice further includes a second adhesive layer disposed between thetouch sensing layer and the light guide member.

In an embodiment of the disclosure, the above-mentioned touch displaydevice further includes a second adhesive layer and a cover plate. Thesecond adhesive layer is disposed on the touch sensing layer, and thecover plate is disposed on the second adhesive layer.

In an embodiment of the disclosure, the ground shielding layer of theabove-mentioned touch display device is located between the light guidemember and the reflective display module.

In an embodiment of the disclosure, the ground shielding layer of theabove-mentioned touch display device is located between the light guidemember and the touch sensing layer.

In an embodiment of the disclosure, the above-mentioned touch displaydevice further includes a light source. The light source is disposed onone side of the light guide member, and is adapted for emitting lighttoward the light guide member.

Based on the above, in the embodiments of the disclosure, by disposingthe ground shielding layer between the reflective display module and thetouch sensing layer, the signal of the reflective display module may beprevented from affecting the touch sensing layer. Thus, the touchsensing layer may have a good touch sensing function. In addition, inthe disclosure, the ground shielding layer is directly integrated on thelight guide member. Therefore, adding other film layers is not required,and the thickness of the touch display device may be further reduced,thereby facilitating the lightness and thinness of the touch displaydevice.

In order to make the aforementioned features and advantages of thedisclosure comprehensible, embodiments accompanied with drawings aredescribed in detail as follows.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a schematic cross-sectional view of a touch display deviceaccording to an embodiment of the disclosure.

FIG. 1B is a schematic cross-sectional view of a touch display deviceaccording to another embodiment of the disclosure.

FIG. 2 is a schematic cross-sectional view of a touch display deviceaccording to still another embodiment of the disclosure.

FIG. 3A is a schematic cross-sectional view of a touch display deviceaccording to yet another embodiment of the disclosure.

FIG. 3B is a schematic cross-sectional view of another embodiment of thetouch display device of FIG. 3A.

FIG. 4 is a schematic cross-sectional view of a touch display deviceaccording to yet another embodiment of the disclosure.

DESCRIPTION OF THE EMBODIMENTS

In the following embodiments, wordings used to indicate directions, suchas “up,” “down,” “front,” “back,” “left,” and “right,” merely refer todirections in the accompanying drawings. Therefore, the directionalwordings used are regarded as illustrative rather than restrictive ofthe disclosure.

In the accompanying drawings, the drawings illustrate the generalfeatures of the methods, structures, and/or materials used in theparticular embodiments. The drawings shall not be interpreted asdefining or limiting the scope or nature covered by the embodiments. Forexample, the relative size, thickness, and location of film layers,regions, and/or structures may be reduced or enlarged for clarity.

In the following embodiments, the same or similar elements will bedesignated by the same or similar reference numerals, and descriptionsthereof will be omitted. In addition, the features of differentembodiments may be combined with each other when they are not inconflict, and simple equivalent changes and modifications made accordingto the specification or the claims are still within the scope of thedisclosure.

The terms such as “first” and “second” mentioned in the specification orthe claims are only used to name discrete elements or to distinguishdifferent embodiments or scopes and are not intended to limit the upperor lower limit of the number of the elements, nor are they intended tolimit the manufacturing order or disposition order of the elements.Furthermore, the disposition of an element/film layer on (or over)another element/film layer may encompass the situation where theelement/film layer is disposed directly on (or over) the otherelement/film layer, and the two elements/film layers are in contact witheach other; and the situation where the element/film layer is indirectlydisposed on (or over) the other element/film layer, and one or moreelements/film layers exist between the two elements/film layers.

FIG. 1A is a schematic cross-sectional view of a touch display deviceaccording to an embodiment of the disclosure. Referring to FIG. 1A, atouch display device 100 a includes a reflective display module 110, atouch sensing layer 120, a light guide member 130, a ground shieldinglayer 140, and a first adhesive layer 150. The touch sensing layer 120is disposed on a display surface 110S of the reflective display module110, and the light guide member 130 is disposed between the reflectivedisplay module 110 and the touch sensing layer 120. The ground shieldinglayer 140 is in contact with the light guide member 130 and locatedbetween the reflective display module 110 and the touch sensing layer120. The ground shielding layer 140 electrically connects to the touchsensing layer 120, so as to electrically connect to a ground potentialGND through the touch sensing layer 120. The first adhesive layer 150 isdisposed between the light guide member 130 and the reflective displaymodule 110, and is located between the ground shielding layer 140 andthe reflective display module 110.

The reflective display module 110 presents a display image by reflectingambient light or the illumination light provided by a front lightmodule. The reflective display module 110 may be a liquid crystal onsilicon (LCOS) panel, other types of reflective liquid crystal panels,or an electronic paper display. The electronic paper display may includean electrophoretic display (EPD) with particle imaging, a quick responseliquid powder display (QR-LPD), a cholesteric liquid crystal display(Ch-LCD), a bistable nematic liquid crystal display (BiNem), or anelectrochromic display (ECD), etc., and the disclosure is not limitedthereto. In the embodiment, the reflective display module 110 adopts theelectrophoretic display (EPD) as an exemplary illustration.

Further, as shown in FIG. 1A, the reflective display module 110 includesan electronic ink film layer 111, a first conductive layer 112, a secondconductive layer 113, and a pixel circuit layer 114. The electronic inkfilm layer 111 is disposed between the first conductive layer 112 andthe second conductive layer 113, and the pixel circuit layer 114 isdisposed on the side away from the display surface 110S, andelectrically connects to the first conductive layer 112 and the secondconductive layer 113. The pixel circuit layer 114 includes signal lines,active elements, passive elements, etc., and may be integrated on aflexible printed circuit (FPC) (not shown). The active element in thepixel circuit layer 114 is, for example, a thin film transistor (TFT),and the passive element is, for example, a capacitor structure, but thetwo elements are not limited thereto. The pixel circuit layer 114 mayprovide corresponding driving signals to generate an electric fieldbetween the first conductive layer 112 and the second conductive layer113, so as to control the positions of particles within a microcapsuleor microcup of different colors (such as white or black or other colors)in the electronic ink film layer 111 to generate a display image. Thefirst conductive layer 112 and the second conductive layer 113 are, forexample, transparent conductive materials, such as indium oxide, tinoxide, indium tin oxide, or indium zinc oxide, but the disclosure is notlimited thereto. Although not shown in the figure, the reflectivedisplay module 110 may further include a substrate carrying the firstconductive layer 112, the second conductive layer 113, and the pixelcircuit layer 114.

The touch sensing layer 120 is disposed on the reflective display module110 by, for example, bonding. That is to say, the touch sensing layer120 may be fabricated independently and then integrated with thereflective display module 110 by bonding. Although not shown in thefigure, the touch sensing layer 120 may include a substrate, sensingelectrodes, and sensing lines (not shown). The sensing electrodes andthe sensing lines may be transparent conductive materials, such asindium oxide, tin oxide, indium tin oxide, or indium zinc oxide, fordetecting the touch action of a user. The touch sensing layer 120 may beany capacitive touch sensing layer (e.g., a self-capacitive or mutualcapacitive touch sensing layer) known to those of ordinary skill in theart for a touch sensing substrate or other forms of touch sensing layers(e.g., resistive or electromagnetic touch sensing layers), which is notlimited in the disclosure.

The ground shielding layer 140 is disposed between the reflectivedisplay module 110 and the touch sensing layer 120, and may be used toshield signal interference between the reflective display module 110 andthe touch sensing layer 120. In addition, the ground shielding layer 140may electrically connect to the touch sensing layer 120 and electricallyconnect to the ground potential GND through the touch sensing layer 120.Such a configuration further helps to discharge excess charges toprotect the touch sensing layer 120 and the reflective display module110 from damage caused by static electricity. In other unillustratedembodiments, the ground shielding layer 140 may also electricallyconnect to the pixel circuit layer 114 of the reflective display module110 to connect to the ground potential GND through the reflectivedisplay module 110.

The light guide member 130 includes a light guide plate 131 and a lowrefractive index layer, and the low refractive index layer may bedisposed on at least one surface of the light guide plate 131. In theembodiment, the low refractive index layer includes a first lowrefractive index layer 132. The first low refractive index layer 132 isdisposed on the light guide plate 131, and the refractive index of thefirst low refractive index layer 132 is smaller than the refractiveindex of the light guide plate 131.

The first low refractive index layer 132 is disposed between the groundshielding layer 140 and the light guide plate 131. The first lowrefractive index layer 132 in the embodiment may be selected from lowrefractive index resin, and the refractive index of the light guideplate 131 is greater than the refractive index of the first lowrefractive index layer 132. In some embodiments, the material of thelight guide plate 131 includes, for example, thermoplastic polymers suchas polymethyl methacrylate (PMMA), cycloolefin (COC), or polycarbonate(PC). The material of the light guide plate 131 may selectively have alower composite refractive index for helping to avoid the rainbowpattern formed by unnecessary optical interference, but is not limitedthereto. For example, the refractive index of the light guide plate 131is approximately 1.58. The refractive index of the first low refractiveindex layer 132 needs to be smaller than the refractive index of thelight guide plate 131, for example, greater than or equal to 1.32 andless than or equal to 1.43. The disclosure does not limit the value ofthe refractive index of the light guide plate 131 as long as the valueis greater than the refractive index of the first low refractive indexlayer 132.

The light guide plate 131 of the embodiment has a light incident surface131 i, a first surface 131 b, and a second surface 131 e. The firstsurface 131 b and the second surface 131 e connect to the light incidentsurface 131 i and are opposite to each other. The first low refractiveindex layer 132 is disposed on the first surface 131 b, and the touchsensing layer 120 is disposed on one side of the second surface 131 e.Moreover, the first surface 131 b has multiple optical microstructuresMS disposed between the light guide plate 131 and the first lowrefractive index layer 132. For example, the optical microstructures MSmay be dot structures formed by ink printing or concave structuresfabricated by injection molding or thermoforming, and thecross-sectional contours of the optical microstructures MS are, forexample, circular, oval, or zigzag shapes, etc., and the disclosure isnot limited thereto. In the embodiment, the optical microstructures MSmay be dot structures and covered by the first low refractive indexlayer 132.

The touch display device 100 a of the embodiment further includes alight source 160. The light source 160 is disposed on one side of thelight incident surface 130 i of the light guide plate 131, and isadapted for emitting light toward the light guide member 130. Thereflective display module 110 provides display light by reflectingambient light as illumination light. Therefore, when the ambient lightis insufficient (such as a dark room), a problem of insufficient displaylight occurs. In the embodiment, by disposing the light source 160 andmatching the light guide member 130, the required illumination light maybe provided or supplemented when the ambient light is weak.

When the light emitted by the light source 160 enters the light guideplate 131 from the light incident surface 131 i, due to the situationwhere the refractive index of the light guide plate 131 is greater thanthe refractive index of the first low refractive index layer 132disposed on the first surface 131 b, generating total internalreflection (TIR) for a part of the light is facilitated, so that thelight may be easily transmitted to the entire light guide member 130after entering the first surface 131 b. Therefore, the first lowrefractive index layer 132 helps to improve the uniformity of lightdistribution. In addition to scattering light, the opticalmicrostructures MS may also destroy total internal reflection, so that apart of the light emitted by the light source 160 from the lightincident surface 131 i is scattered from the first surface 131 b throughthe optical microstructures MS and irradiates to the reflective displaymodule 110 while being transmitted through total internal reflection inthe light guide plate 131. The reflective display module 110 reflectsthe display light, so that the reflected display light passes throughthe ground shielding layer 140, the first low refractive index layer132, and the light guide 130 in sequence and exits through the secondsurface 131 e. In addition, the distribution density of the opticalmicrostructures MS may be increased in the direction away from the lightsource 160, so as to increase the output ratio of light in the portionof the light guide plate 131 away from the light incident surface 131 i,whereby the brightness of the light guide member 130 is more uniform andconsistent.

The light source 160 may be a combination of multiple light emittingdiodes (LEDs). The light emitting diode is, for example, asub-millimeter light emitting diode (mini LED) or a micro light emittingdiode (micro LED). Since the light source 160 of the disclosure is usedto provide or supplement the illumination light required when theambient light is weak, the light source 160 is preferably a white lightsource. The white light source may be directly composed of white lightemitting diodes or utilize wavelength conversion materials to convertthe light emitted by non-white light emitting diodes (such as blue lightor ultraviolet light) into color light (such as red light, green light,or blue light) that may be mixed into white light. The wavelengthconversion material is, for example, yellow fluorescent powder(Y₃Al₅O₁₂:Ce³⁺, YAG) or fluoride fluorescent powder (K₂SiF₆:Mn4⁺, KSF),but the disclosure is not limited thereto.

It is worth mentioning that the thickness Tm of the opticalmicrostructures MS is smaller than the thickness T1 of the first lowrefractive index layer 132. Such a design may facilitate the dispositionand uniform distribution of the ground shielding layer 140, as well asthe flattening of the interface between the first low refractive indexlayer 132 and the ground shielding layer 140, so as to prevent unwantedrefraction and reflection from interfering with the transmission of thedisplay light.

Moreover, the ground shielding layer 140 is directly formed on the lightguide member 130. Further, the ground shielding layer 140 in theembodiment is formed on the first low refractive index layer 132 andbonded to the display surface 110S of the reflective display module 110through the first adhesive layer 150. That is to say, the groundshielding layer 140 of the touch display device 100 a of the embodimentis located between the light guide member 130 and the reflective displaymodule 110. The material of the ground shielding layer 140 may includeconductive oxides with high visible light transmittance such as indiumzinc oxide, indium tin oxide (ITO), and the like. The manufacturingmethod of the ground shielding layer 140 may be realized by usingprocess methods known to those of ordinary skill in the art, includingthe deposition method and the sputter deposition method, and thedisclosure is not limited thereto.

By disposing the ground shielding layer 140 between the reflectivedisplay module 110 and the touch sensing layer 120 and electricallyconnecting the ground shielding layer 140 to the ground potential GND,the signals of the reflective display module 110 may be prevented frominterfering with the touch sensing layer 120. Thus, the touch sensinglayer 120 may have a good touch sensing function. Moreover, in theembodiment, the ground shielding layer 140 is directly formed on thefirst low refractive index layer 132, thereby integrating the groundshielding layer 140 into the light guide member 130. Therefore, addingother film layers is not required, and the thickness of the touchdisplay device 100 a may be further reduced, thereby facilitating thelightness and thinness of the touch display device 100 a.

The touch display device 100 a may use the first adhesive layer 150 tobond the light guide member 130 to the reflective display module 110.Besides, the touch display device 100 a further includes a secondadhesive layer 151 disposed between the touch sensing layer 120 and thelight guide member 130. More specifically, the touch sensing layer 120may be attached to the second surface 131 e of the light guide plate 131through the second adhesive layer 151. The materials of the firstadhesive layer 150 and the second adhesive layer 151 include opticalclear adhesive (OCA), optical pressure sensitive adhesive (PSA),polyurethane reactive (PUR) adhesive, polyurethane (PU) adhesive, orother suitable optical grade adhesive materials. In particular, thematerial of the adhesive layer may be selected from an optical adhesivematerial with high transmittance (such as optical clear adhesive). Forexample, in the embodiment, the visible light transmittance of the firstadhesive layer 150 and the second adhesive layer 151 may be greater than99%, but is not limited thereto.

The touch display device 100 a further includes a cover plate 170 and athird adhesive layer 152. The cover plate 170 is attached to the touchsensing layer 120 through the third adhesive layer 152. The material ofthe cover plate 170 is, for example, glass, quartz, or other suitablemacromolecule polymers (such as polycarbonate). The material of thethird adhesive layer 152 may be the same as the materials of the firstadhesive layer 150 and the second adhesive layer 151, and is notrepeated here.

The above-mentioned first adhesive layer 150, second adhesive layer 151,and third adhesive layer 152 are only used for illustrative descriptionof the quantity, and are not used to limit the difference in the typesof elements.

Other embodiments are described below to explain the disclosure indetail, and the same components will be denoted by the same referencenumerals, and the description of the same technical content will beomitted. For the description of the omitted part, reference may be madeto the above embodiment, and details are not described in the followingembodiments.

FIG. 1B is a schematic cross-sectional view of a touch display deviceaccording to another embodiment of the disclosure. Referring to FIG. 1B,a touch display device 100 b of the embodiment is similar to the touchdisplay device 100 a of FIG. 1A. The touch display device 100 b includesa reflective display module 110, a touch sensing layer 120, a lightguide member 130, a ground shielding layer 140, a first adhesive layer150, a second adhesive layer 151, a light source 160, a cover plate 170,and a third adhesive layer 152. The difference between the touch displaydevice 100 b and the touch display device 100 a of FIG. 1A is that theconfiguration position of the ground shielding layer 140 is different.Specifically, the ground shielding layer 140 of the touch display device100 a is disposed between the display surface 110S and the first lowrefractive index layer 132, but the ground shielding layer 140 of thetouch display device 100 b of the embodiment is located between thelight guide member 130 and the touch sensing layer 120.

Further, the ground shielding layer 140 of the touch display device 100b is disposed between the light guide plate 131 and the second adhesivelayer 151. Since the material selected for the ground shielding layer140 in the embodiment may be ITO, and such a material has a highabsorption rate in the ultraviolet wavelength band, in addition toachieving the aforementioned signal shielding effect, the groundshielding layer 140 may further protect the light guide plate 131 formedof polymers, multiple optical microstructures MS, and the first lowrefractive index layer 132 from being irradiated by ambient ultravioletlight and degraded.

FIG. 2 is a schematic cross-sectional view of a touch display deviceaccording to still another embodiment of the disclosure. Referring toFIG. 2 , a touch display device 100 c of the embodiment is similar tothe touch display device 100 a of FIG. 1A. The touch display device 100c includes a reflective display module 110, a touch sensing layer 120, alight guide member 130, a ground shielding layer 140, a first adhesivelayer 150, a light source 160, a cover plate 170, and a third adhesivelayer 152. The difference between the touch display device 100 c and thetouch display device 100 a of FIG. 1A is that the light guide member 130of the touch display device 100 c further includes a second lowrefractive index layer 133 in contact with the touch sensing layer 120and the light guide plate 131, and the touch display device 100 c is notdisposed with a second adhesive layer 151. In addition, the touchsensing layer 120 is, for example, in contact with the light guidemember 130.

Specifically, in the touch display device 100 c of the embodiment, thefirst low refractive index layer 132 and the second low refractive indexlayer 133 are disposed on the first surface 131 b and the second surface131 e of the light guide plate 131, respectively. The materials of thefirst low refractive index layer 132 and the second low refractive indexlayer 133 may be the same or different as long as the refractive indexof the light guide plate 131 is greater than the refractive indexes ofthe first low refractive index layer 132 and the second low refractiveindex layer 133. However, the disclosure is not limited thereto. Inaddition, the thickness T2 of the second low refractive index layer 133and the thickness T1 of the first low refractive index layer 132 may bethe same as each other.

In summary, since the first low refractive index layer 132 and thesecond low refractive index layer 133 are respectively disposed on thefirst surface 131 b and the second surface 132 e of the light guideplate 131 of the touch display device 100 c, in addition to theaforementioned advantages of the touch display device 100 a, the lightguide effect of the light guide plate 131 may be further increased.

Moreover, the touch sensing layer 120 of the embodiment may be directlyfabricated on the second low refractive index layer 133 of the lightguide member 130, and then the cover plate 170 may be attached to thetouch sensing layer 120 by using the third adhesive layer 152. Themethod of fabricating the touch sensing layer 120 may be to form aconductive layer on the second low refractive index layer 133 bychemical vapor deposition (CVD) or physical vapor deposition (PVD) orother methods, and then selectively cooperate with the patterningprocess (such as lithography, etching, etc.) to form the correspondingsensing electrodes and the required insulating layer, so that the touchsensing layer 120 is directly fabricated on the second low refractiveindex layer 133 of the light guide member 130. In other words, in theembodiment, the touch sensing layer 120 is directly integrated on thelight guide member 130, so that no additional bonding layer is requiredbetween the touch sensing layer 120 and the light guide member 130. Sucha configuration may reduce the use of bonding materials and the steps ofthe manufacturing process, improve yield, and reduce production costs.

FIG. 3A is a schematic cross-sectional view of a touch display deviceaccording to yet another embodiment of the disclosure. Referring to FIG.3A, a touch display device 100 d of the embodiment is similar to thetouch display device 100 a of FIG. 1A. The touch display device 100 dincludes a reflective display module 110, a touch sensing layer 120, alight guide member 130, a ground shielding layer 140, a first adhesivelayer 150, a second adhesive layer 151, a light source 160, a coverplate 170, and a third adhesive layer 152. The difference between thetouch display device 100 d and the touch display device 100 a of FIG. 1Ais that multiple optical microstructures MS of the touch display device100 d are disposed on the second surface 131 e of the light guide plate131.

Further, in the embodiment, the optical microstructures MS are disposedon the second surface 131 e of the light guide plate 131, and theoptical microstructures MS are covered by the second adhesive layer 151.In this way, when irradiating to the second surface 131 e, the lightentering the light guide plate 131 from the light incident surface 131 iis scattered by the optical microstructures MS, returns to the firstsurface 131 b of the light guide plate 131, and irradiates to thereflective display module 110 to provide enough light for display.

FIG. 3B is a schematic cross-sectional view of another embodiment of thetouch display device of FIG. 3A. Referring to FIG. 3B, a touch displaydevice 100 e of the embodiment is similar to the touch display device100 d of FIG. 3A. The touch display device 100 e includes a reflectivedisplay module 110, a touch sensing layer 120, a light guide member 130,a ground shielding layer 140, a first adhesive layer 150, a secondadhesive layer 151, a light source 160, a cover plate 170, and a thirdadhesive layer 152. The difference between the touch display device 100e and the touch display device 100 d of FIG. 3A is that theconfiguration position of the ground shielding layer 140 is different.Specifically, the ground shielding layer 140 of the touch display device100 d is disposed between the display surface 110S and the first lowrefractive index layer 132. However, the ground shielding layer 140 ofthe touch display device 100 e of the embodiment is disposed on thesecond surface 131 e of the light guide plate 131 and covers multipleoptical microstructures MS.

Since the ground shielding layer 140 of the touch display device 100 eis disposed on the second surface 131 e of the light guide plate 131, asimilar effect to the aforementioned touch display device 100 b may alsobe achieved, which is not repeated here. In addition, by covering theground shielding layer 140 and the optical microstructures MS with thesecond adhesive layer 151, increasing the flatness of disposing elementsin subsequent processes is facilitated, so as to prevent unwantedrefraction and reflection from interfering with the transmission ofdisplay light.

FIG. 4 is a schematic cross-sectional view of a touch display deviceaccording to yet another embodiment of the disclosure. Referring to FIG.4 , a touch display device 100 f of the embodiment is similar to thetouch display device 100 c of FIG. 2 . The touch display device 100 fincludes a reflective display module 110, a touch sensing layer 120, alight guide member 130, a ground shielding layer 140, a first adhesivelayer 150, a light source 160, a cover plate 170, and a third adhesivelayer 152. The difference between the touch display device 100 f and thetouch display device 100 c of FIG. 2 is that multiple opticalmicrostructures MS of the touch display device 100 f are disposed on thesecond surface 131 e of the light guide plate 131, and the second lowrefractive index layer 133 covers the optical microstructures MS. Thus,the touch display device 100 f of the embodiment may have the advantagesof both the touch display device 100 c in FIG. 2 and the touch displaydevice 100 d in FIG. 3A, which are not repeated here.

In summary, in the embodiment of the disclosure, by disposing the groundshielding layer between the reflective display module and the touchsensing layer, the signal of the reflective display module may beprevented from affecting and/or interfering with the sensing function ofthe touch sensing layer. Thus, the touch sensing layer may have a goodtouch sensing function. In addition, in the disclosure, the groundshielding layer is directly integrated on the light guide member.Therefore, adding other film layers is not required, and the thicknessof the touch display device may be further reduced, thereby facilitatingthe lightness and thinness of the touch display device.

Although the disclosure has been described with reference to the aboveembodiments, the described embodiments are not intended to limit thedisclosure. People of ordinary skill in the art may make some changesand modifications without departing from the spirit and the scope of thedisclosure. Thus, the scope of the disclosure shall be subject to thosedefined by the attached claims.

What is claimed is:
 1. A touch display device, comprising: a reflectivedisplay module having a display surface; a touch sensing layer disposedon the display surface; a light guide member disposed between thereflective display module and the touch sensing layer; a groundshielding layer in contact with the light guide member and locatedbetween the reflective display module and the touch sensing layer, andthe ground shielding layer electrically connecting to one of thereflective display module and the touch sensing layer to electricallyconnect to a ground potential through the one of the reflective displaymodule and the touch sensing layer; and a first adhesive layer disposedbetween the light guide member and the reflective display module, andlocated between the ground shielding layer and the reflective displaymodule.
 2. The touch display device according to claim 1, wherein thelight guide member comprises a light guide plate and a low refractiveindex layer, the low refractive index layer is disposed on the lightguide plate, and a refractive index of the low refractive index layer issmaller than a refractive index of the light guide plate.
 3. The touchdisplay device according to claim 2, wherein the ground shielding layeris in contact with the low refractive index layer.
 4. The touch displaydevice according to claim 2, wherein the light guide plate has a lightincident surface, a first surface, and a second surface, the firstsurface and the second surface connect to the light incident surface andare opposite to each other, and at least one of the first surface andthe second surface has a plurality of optical microstructures.
 5. Thetouch display device according to claim 4, wherein thickness of the lowrefractive index layer is greater than thickness of the plurality ofoptical microstructures.
 6. The touch display device according to claim5, wherein the low refractive index layer comprises a first lowrefractive index layer and a second low refractive index layer, and thefirst low refractive index layer and the second low refractive indexlayer are disposed on the first surface and the second surface of thelight guide plate, respectively.
 7. The touch display device accordingto claim 1, further comprising: a second adhesive layer disposed betweenthe touch sensing layer and the light guide member.
 8. The touch displaydevice according to claim 1, wherein the touch sensing layer is incontact with the light guide member.
 9. The touch display deviceaccording to claim 1, further comprising: a second adhesive layerdisposed on the touch sensing layer; and a cover plate disposed on thesecond adhesive layer.
 10. The touch display device according to claim1, wherein the ground shielding layer is located between the light guidemember and the reflective display module.
 11. The touch display deviceaccording to claim 1, wherein the ground shielding layer is locatedbetween the light guide member and the touch sensing layer.